1. Field of Invention
The present invention relates to a mobile communication device, and more particularly to a buffer protection structure which is used to limit displacement of and protect a light tube used as a flat light-emitting element of a display panel in a mobile communication device.
2. Related Art
Throughout the rapid progression and evolution of display technology, conventional CRT (cathode ray tube) displays have been replaced gradually by liquid crystal display because of volume and energy consumption. With advantages of high display quality, low energy consumption and zero radiation, etc., the liquid crystal display can be applied broadly in 3C (Computing, Communication and Consumer) products, such as a mobile phone (or cellular phone), a personal digital assistant, a laptop computer, a digital camcorder, a digital camera, a computer screen and a liquid crystal TV.
The liquid crystal display uses primarily a liquid crystal panel to display. As the liquid crystal panel is a non-spontaneous light-emitting display panel, a backlight module or a flat light-emitting element has to be used to supply a light source which provides sufficient brightness and is uniform distribution, such that the liquid crystal panel can display an image normally. The backlight module, for example, is ordinarily assembled by a cold cathode fluorescent light tube, a light guide plate and a reflector, wherein the backlight module can be divided into a direct-type backlight module (or flat-type backlight module) with a light source being generated from a direct lower side of the display panel or an edge-type backlight module with a light source being generated from a location close to a side of the display panel, according to the location of light source.
Referring to FIG. 1, it shows a drawing of a conventional protection structure for a light tube which serves as a light source of a display panel, wherein a cellular phone M includes a housing M1, a flat light-emitting element M2 and a protection structure M3. The flat light-emitting element M2 may be a backlight module having a cold cathode light tube as a light source or a flat cold cathode light tube, and is provided in the housing M1. The protection structure M3 is a rigid rectangular frame which encloses the flat light-emitting element M2 and is abutted at inner walls of the housing M1 to limit displacement of and protect the flat light-emitting element M2.
However, in such a simple rectangular protection structure, a side surface of a flat light-emitting element in a cellular phone, such as a flat light tube, touches rigidly with the protection structure; whereas, for a flat light-emitting element such as a backlight module, all the backlight modules are made of a fragile plastic material, and as the light tube which is provided in the backlight module is smaller in size, it is relatively fragile; yet the side surface of the light tube still touches rigidly with the protection structure in an indirect way. Nevertheless, a most fragile part in glass of the light tube is the side surface; therefore, the pure rigid protection structure is disadvantageous to absorb lateral impact. Moreover, four corners of the light tube where stress is concentrated most easily collide more easily with the protection structure to rupture the light tube.